Relation of Mass to JEmergy. 15 
table of atomic weights becomes a well-nigh insuperable 
difficulty in the path of the evolutionary theory of the 
elements. 
If we follow the present suggestion, we must search for 
the components of an element, not by comparing atomic 
weights, but by comparing the corresponding values of N, 
for the atomic weights deviate because of the lost mass 
accompanying the dissipation of internal energy. 
Very recently Sir W. Ramsay has announced several 
striking discoveries which seem to add much weight to the dis- 
integration theory, and, indirectly, to the views here set forth. 
He found helium, neon, or argon appearing as a product of 
radium emanation according to the exterior conditions 
imposed, and he found lithium appearing when a copper- 
sulphate solution was left in the presence of the emanation. 
Prof. Ramsay states. I believe, that every source of error 
was eliminated and that the results were obtained many 
times. I 
11. It should be noticed that this theory of loss of mass 
and its consequences does not require that the whole material 
mass should be of electromagnetic nature. It only requires 
that the energy lost in the transformations, explosive or 
otherwise, should be at the expense of internal electromagnetic 
energy, i. <?., that the forces which expel the a-par tides should 
be electric or magnetic. 
■» 
Respecting Gra vitation. 
15. The experiments of many investigators have shown 
that up to a high degree of accuracy the ratio of mass to 
weight for different substances is the same. Xow if the 
mass is proportional to the internal energy as here suggested, 
instead of being proportional to the number of electric nuclei 
as might be supposed, the conclusion is apparently forced 
upon us that gravitational attraction is between quantities of 
confined energy, and not between quantities of " matter " in 
any other sense. 
On this basis, the weight of a calorie at the earth's surface 
would be of order 10~ n dyne. This is apparently too small 
to explain the temperature gradient in the earth although the 
calculation, depending as it does on the mechanical force on 
confined energy due to a temperature gradient, would certainly 
depend to a large degree on the medium. 
If we assume this gravitational effect, it is interesting to 
ask whether free energy would also show an attraction for 
itself. If so, the energy radiated from a gravitational centre 
like the sun would leave some of itself behind along its path 
